Moving file remotly deletes it locally and remove av. offline flag

[theScrabi]

Basically all the local information about a file is lost when its moved remotely. This is because the client does not now weather the file has been deleted or just moved. In order to support keeping the file locally the client had to ask the server what happened to the file.

[michaelstingl]

@jesmrec could you verify with oC server 10.0.8+ ? (owncloud/core#29021 + owncloud/core#30383)